<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style type="text/css">
        /*css代码*/
        span {
            color:red;
        }
    </style>
</head>
<body>
<span>我是一段文字</span>
<p>我是一段文字</p>
</body>
</html>